18922172 has 12 divisors (see below), whose sum is σ = 33208560. Its totient is φ = 9434016.

The previous prime is 18922171. The next prime is 18922177. The reversal of 18922172 is 27122981.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18922171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5153 + ... + 8024.

It is an arithmetic number, because the mean of its divisors is an integer number (2767380).

Almost surely, 2^18922172 is an apocalyptic number.

It is an amenable number.

18922172 is a deficient number, since it is larger than the sum of its proper divisors (14286388).

18922172 is a wasteful number, since it uses less digits than its factorization.

18922172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13540 (or 13538 counting only the distinct ones).

The product of its digits is 4032, while the sum is 32.

The square root of 18922172 is about 4349.9622986872. The cubic root of 18922172 is about 266.4753217623.

The spelling of 18922172 in words is "eighteen million, nine hundred twenty-two thousand, one hundred seventy-two".